Research On Message Authentication Scheme For Vehicular Ad-hoc Networks

Traffic accidents have been happening all over the world in recent years,which have become one of the serious problems facing all mankind.Vehicular ad-hoc networks(VANETs)is a high-speed mobile wireless self-organizing network,which have become an important foundation of intelligent transportation.Thus VANETs can minimize or avoid traffic accidents,improve traffic efficiency,and ameliorate the riding environment by communicating between vehicles and roadside units,vehicles and vehicles.Because of the openness and vulnerability of wireless networks,messages transmitted in VANETs are vulnerable to forgery or tampering attacks.In addition,vehicles in the VANETs move at high speed,and the bandwidth of communication are very limited,which require that message authentication in the VANETs must have lower communication overhead.If the ordinary digital signature scheme is used to verify the message one by one,it is unavoidable that some important information can not be authenticated within the effective time,thereby causing economic losses to the vehicle users and even endangering their life safety.In response the problems of overhead of message authentication,low communication efficiency and privacy in VANETs,three message authentication schemes in VANETs are proposed by using the techniques of trapdoor hash function,batch processing verification,and server-assisted verification signature,proxy re-signature,identity-based signature and other cryptosystems.(1)To solve the problems of identity privacy and excessive message authentication overhead in VANETs,a new message authentication scheme is created based on the proxy re-signature and trapdoor hash function.It efficieatly solves presented the problems of identity anonymity and traceability of the message communication,and greatly improves the real-time performance of the communication message and the verification efficiency of the signature.(2)To reduce the computational overhead of the verifier,a server-assisted verification proxy re-signature is introduced,and a new type of VANETs message authentication scheme is presented.The verifier delegates most of the computational tasks to a third-party server,and only a small amount of computation is needed to complete the validity verification of the signature.The proposed scheme realizes the anonymity of the vehicle identity and the traceability of the communication message,and efficiently reduces the computational overhead of the verifier.(3)To solve the problem of excessive certificate management overhead in traditional public key cryptosystem,an identity-based message authentication scheme in VANETs is designed using identity-based aggregate signature technology.With the help of the scheme,many signatures from variable users can be aggregated into a short signature,which greatly improves the efficiency of signature verification and eases the transmission bandwidth.The analysis results show that the security of the new scheme depends on the computational Diffie-Hellman problem under the random oracle model.Compared with similar schemes,the proposed scheme has higher security performance.